The present invention concerns a method of directional distribution of allocation in two-way alternate line bundles.
Related Technology
Line bundles in voice and data networks switched between computer-controlled exchange facilities are generally operated as two-way alternate lines. In this operating mode, both exchange facilities independently of one another can access free lines of the bundle and occupy them. The full capability of the line bundle is utilized in this way. However, with this operating mode there is the risk that when one direction of traffic is temporarily dominant, traffic flow in the other direction may be hindered or even displaced. The grade of service in this direction is thereby greatly reduced.
Two traffic management methods for preventing such displacement are known. The first method operates by introducing the traffic management function xe2x80x9ctrunk reservationxe2x80x9d and in the second method by dividing the traffic connection in question three ways.
In xe2x80x9ctrunk reservationxe2x80x9d one direction of traffic is preferred in that the last free line is kept free for this direction. This means that only the preferred direction can have access to the last free line. Thus, given the same starting situation, a requested connection in the direction that is not protected would be rejected and would thus fail.
The trunk reservation method yields the disadvantage that only one direction is protected, and traffic in the other direction can be displaced when the protected direction has a similarly high demand.
A method for democratically protecting both directions from displacement by the other direction is a three-way division of the traffic relationship in question. The lines of a bundle are divided into three partial bundles as follows: a directionally operated partial bundle for the basic traffic of the outgoing direction, a directionally operated partial bundle for the basic traffic of the incoming direction, and a partial bundle with two-way alternate operation which can be used in both directions by peak traffic.
When traffic in one direction is dominant, displacement of the traffic from the opposite direction can with the second method occur in the two-way alternate partial bundle but not in the directional partial bundle in the opposite direction.
A disadvantage of this operating mode is that full capability of a two-way alternate line bundle cannot be achieved. Thus, more lines are needed for handling a certain amount of traffic than are actually necessary.
Prior traffic management methods are summarized and described in principle in CCITT Recommendation E.412 xe2x80x9cNetwork Management Controlsxe2x80x9d (10/92) by INTERN: TELECOMMUNICATION UNION.
An object of the present invention is to ensure the full capability of a two-way alternate bundle while at the same time precluding mutual displacement for both directions of traffic.
Therefore, an object of the present invention is to create a method of directional distribution of allocation in two-way alternate line bundles arranged between computer-controlled exchange facilities that will ensure full capability of the two-way alternate line bundle, preclude mutual displacement of the traffic in both directions and make the division ratio on one line adaptable exactly to the actual conditions.
The measure proposed according to the present invention is characterized in particular in the characterizing part of Patent Claim 1.
Additional features of the present invention and embodiments are derived from the characterizing parts of Patent Claims 2 through 6 which follow Patent Claim 1.
Advantages of the traffic management according to the present invention include that the full capability of the two-way alternate operating mode is utilized, and displacement in favor of one.
The method according to the present invention thus permits savings in numbers of lines and results in a balanced traffic distribution between the outgoing and incoming traffic of a line bundle and thus to an improvement in the grade of servicexe2x80x94even under unusual traffic conditions.